1. Field of Invention
The current invention relates generally to apparatus, systems and methods related to optics. More particularly, the apparatus, systems and methods relate to optics used in cameras. Specifically, the apparatus, systems and methods provide for a photochromic filter which reacts to Ultra-Violet (UV) light, reduces the transmission through the camera optics in bright sunlight; thereby extending the exposure range of the camera without the need for a mechanical iris.
2. Description of Related Art
Traditionally, a camera that uses a complementary metal-oxide-semiconductor (CMOS) image sensor that needs to operate over a wide range of light (bright sunlight to ¼ moon illumination) is not capable of providing a full dynamic range of coverage. Cameras in this situation normally would employ variable iris diaphragms to allow widely for varying light conditions. This mechanical solution creates extreme size, weight, and power constraints. For applications such as the Nano Unmanned Aerial Systems (Nano-UAS) and Micro-Unmanned Aerial Systems (MUAS), the size, weight, and power of a mechanical iris is prohibitive. What is needed is a better optics for use in cameras.